Thread positioning mechanism



Jan. 16, 1962 Filed May 31, 1960 w. c. TROST 3,017,128

THREAD POSITIONING MECHANISM 3 Sheets-Sheet 1 Jan. 16, 1962 w. c. TROST 3,017,128

THREAD POSITIONING MECHANISM Filed May 51, 1960 3 Sheets-Sheet 2 5H F INVENTOR.

Mar ne, C. 'Tv'o wt" Jan. 16, 1962 w. c. TROST 3,017,128

THREAD POSITIONING MECHANISM Filed May 51, 1960 3 Sheets-Sheet 3 States This invention relates to a mechanism for positioning a thread in relation to a part for operating on the thread such as the bill of a knotter. For example, in the winding machine disclosed in my copending application, Serial No. 669,234, filed July 1, 1957, a plurality of threads unwound from bobbins on an indexable magazine and supported in generally parallel relation and advanced successively into operative association with the bill of a knotter by which the thread is tied instantaneously to another thread upon exhaustion of the latter and without interrupting the winding operation. In approaching the knotter, an intermediate portion of the thread is intercepted andbent laterally and then positioned properly with respect to the knotter bill and the associated running thread.

The general object is to provide a mechanism of the above general character which will position successive threads quickly and more reliably than has been possible heretofore.

A more detailed object is to effect the thread positioning by the overcenter action of a spring exerted on a crank which is brought to rest in an accurately defined position for receiving a succeeding thread.

The invention also resides in the novel manner of weighting the crank to insure proper association thereof with a locating pawl.

Other objects and advantages of the invention will be come apparent from the following detailed description taken in connection with the accompanying drawings, in which FIGURE 1 is a fragmentary perspective view of part of a winder embodying the novel feature of the present invention.

FIG. 2 is a diagrammatic view of showing the relationship of several threads in the winder.

FIG. 3 is a fragmentary section taken along the line 3-3 of FIGS. 1 and 4.

FIG. 4 is an elevational view of the mechanism shown in FIG. 3.

FIG. 5 is a fragmentary view of the improved thread positioning mechanism and associated parts.

FIG. 6 is a diagrammatic view of the orbit traversed by the thread positioning fingers.

The improved thread positioning mechanism is shown in the drawings incorporated in a winding machine of the type disclosed in the aforesaid application to which reference may be made for details of certain of the parts described below. In this machine, an active bobbin 10 and a plurality of reserve bobbins 11 are mounted in pockets spaced around a magazine 12 fast on an upright shaft 13 which is journaled in spaced bearings 14 and indexable through steps of lengths determined by the angular spacing of bobbins. Lengths of the threads unwound from the reserve bobbins 11 are hung up in inverted J-shape around flanges 15 on a disk 16 fast on the shaft, the short leg 17 of each J being spaced ahead of the long leg 18 and held at its lower end in a spring clamp 13W on the outer periphery of a disk 13 fast on the shaft 13.

During the winding operation the magazine is stationary and the thread 19 of the bobbin 10 is unwound and drawn upwardly through suitable guides illustrated schematically in FIG. 2 and to a package such as a cheese 20 which rests on and is driven by a rotating atent ice winding drum 21. In running past the bill 22 of a knotter 23, the thread 19 is disposed within the heel of the bill and alongside the short leg 17 of the first reserve thread which is bent laterally and outwardly so as to lie against the outer side of the bill and cross the running thread above and below this bill as shown in FIGS. 1, 2 and S. This is accomplished by disposing the running thread in notches 25 and 26 vertically alined with the inside of the knotter heel as shown in FIG. 5 and formed in stationary plates 27 and 28 below and above the bill. The leading end 17 of the reserve thread is disposed in lower and upper notches 29 and 30 formed in the plates 27 and 28 and spaced inwardly from the notches 25 and 26 and like the latter opening along the path of advance of the threads to the knotter but in a direction opposite to the indexing motion.

The bill 22 projects laterally from a shaft 25 journaled on the machine frame at 26 and coupled through gears 27 (FIG. 3) with a shaft 28 which is spring actuated. Upon breaking of the thread, the bill is turned clockwise as viewed in FIG. 6 through at least a revolution and operates instantaneously as described in the aforesaid application to tie the trailing portion of the broken thread to the leg 17 of the first reserve thread and thus continue the winding.

At the same time, an indexing step of the magazine 12 and shaft 13 is initiated during which the leading portion 17 of the second reserve thread is shifted sidewise along a path 34 into proper association above described with the knotter bill. This necessitates intercepting the thread as it approaches the tip 31 of the bill, bending the intervening length of thread outwardly, holding this position of the bend until the thread passes beyond the bill tip, and then releasing the bend to leave the thread crossing the running thread above and below the knotter. Interception of the advancing reserve thread is effected by at least one finger 32 which normally projects transversely of the path of indexing of the thread, there being two such fingers in the present instance respectively spaced above and below the tip 31 of the knotter bill. After such interception, the fingers are shifted outwardly and along the indexing path and then inwardly to describe an orbit 33 which, as shown in FIGS. 3 and 6, lies tangent to the path of advance of the thread and extends outwardly from the latter beyond the knotter bil-l.

To effect the orbital movement, the fingers 32 are formed on and project laterally from the outer end of one leg 34 of a bell crank 38 which is L-shaped in the present intsance and fulcrumed to swing about a floating axis defined by a pivot pin 36, the other end portion of the bell crank being journaled on the pin 37 of a crank which is turned counterclockwise through one revolution from a well-defined position (FIGS. 3 and 4) corresponding to the retracted position of the'fingers 32. The pivot pin 36 is mounted in a yoke 39 (FIG. 5) and projects upwardly from the free end of an arm 46' fulcrumed at its inner end on a pin 41 upstanding from and fixed to a stationary plate 42 in which the thread guide notches 25 and 29 are formed. The arm 40 is spaced inwardly from the path of the thread and projects along this path opposite to the travel of the thread. The arm which is somewhat shorter than the leg 34 of the bell crank 38 thus supports the latter for bodily shifting back and forth about an axis paralleling the crank pin 37. The latter projects through and is fixed on a wheel 43 journaled on a stud 44 on the frame plate 42.

Normally the crank wheel is urged counterclockwise by a spring 45 and held in an angular position corresponding to the retracted position of the fingers 32 and defined by a leaf spring pawl 46 fixed cantilever fashion to the frame at 47 for engagement at its free end with an abutment in the form of a radially disposed shoulder 3 48 on the wheel periphery. The spring is of the contractile type and stretched between the crank pin 37 and the outer end of a fixed arm 49.

The eccentrically disposed crank pin projects through and below the wheel 43 into the path of the teeth 50 angularly spaced around the periphery of a disk 51 fixed to the indexable shaft 13. The leading faces of the teeth are disposed substantially radial and face in the clockwise direction of the shaft indexing. At the proper time in each step of the iatter, one tooth picks up the pin 37 and turns the crank wheel 43 counterclockwise thus further stretching the spring 45. The line of action of the latter is thus moved laterally toward and finally overcenter or across the line L (FIG. 3) whereupon the spring force becomes effective'to turn the wheel on ahead of the cam tooth 50, this force continuing to be applied a full half revolution between the two dead center positions of the crank during which the bell crank 38 is, by rocking of its supporting arm 40, first shifted outwardly and then drawn inwardly.

After the crank pin passes the second dead center position, the spring begins to act in the opposite direction and turns the crank clockwise after the momentum of the par-ts has been overcome. To insure that the crank will always be stopped with the pawl engaging the shoulder 48 under the force of the spring and the fingers properly positioned, the invention contemplates construction of the crank and the connected par-ts with sufficient inertia to insure that the momentum acquired under the action of the spring after the crank has been moved over-center by the cam tooth will be sufiicient to swing the crank far enough beyond the opposite over-center position to carry the shoulder 48 past the tip of the pawl 46. Then, as the turning of the crank under the action of the spring is reversed, the shoulder will come against the pawl end and stop the crank with the fingers 32 in the desired retracted position shown in FIG. 3.

As a result of the crank motion above described and the mounting of the bell crank 38 on the floating arm 40, it will be apparent that in the initial counterclockwise movement of the crank pin by a cam tooth 50 and up to the over-center position of the crank, the fingers 32 are shifted outwardly and transversely of the path of advance of the thread 17 and along the initial quarter revolution after the crank passes over-center. Then, in the remainder of the revolution of the crank, the fingers are retracted back along the straight part of the orbit 33 and the crank comes to rest against the stop pawl.

The teeth 50 of the cam are positioned around the shaft so as to come into engagement with the pin 37 and initiate turning of the crank at the time in the indexing cycle when the advancing thread 17 reaches and is intercepted by the finger 32 which, as shown in full in FIGS. 4 and 6, straddle the knotter bill 22 and project outwardly across the path 34 of advance of the thread to the knotter. In the initial turning of the crank up to the over-center, position the fingers are shifted transversely of the thread path 34 to bend the intervening length of the thread outwardly relative to its stationary guide notches 29 and 30 and along the initial part a (FIG. 6) of the orbit.

Such bending continues in the next quarter revolution of the crank during which the bend in the thread is carried across and beyond the tip 31 of the knotter bill along part b of the orbit. By the simultaneous swinging of the arm 40, the final portion of this motion is along the bill 22 thus carrying the thread to the outer side of the bill as shown in FIG, and in phantom in FIG. 6. The motions of the bill crank 38 and its supporting arm 40 are reversed in the next quarter revolution of the crank during which the fingers 32 are retracted along the straight part c of the orbit and across and away from the thread which is left deposited on the outer side of the knotter bill.

. During the final retraction of the fingers 32 and as the line of action of the spring is carried across the center line L (FIG. 3), the spring force becomes efiective to resist continued turning of the crank. Owing, however, to its substantial inertia, the crank wheel has by this time gained enough momentum to overcome the spring and carry the crank pin counterclockwise beyond its normal rest position thus insuring that the shoulder 48 will always move past the tip of the pawl 46. Then when the fly-wheel effect is dissipated, the spring reverses the turning of the wheel until the shoulder comes against the stop pawl to arrest the motion with all of the parts disposed in the normal rest position and ready for the next thread positioning cycle.

The orbital motion of the positioning fingers 3-2 occupies only a fraction of the indexing motion of the shaft 13 and is completed well before the next tooth 5d of the cam disk approaches the normal position of the crank pin 37. When the indexing is complete the next tooth 50 toactuate the ,crank will be disposed behind and adjacent the crank pin as shown in FIG. 3.

Through the bell crank and inertia type crank wheel it is possible to use a single spring and cam to execute reliably in. accurately timed relation to the thread advance the somewhat complex orbital motion required to effect the desired positioning of the thread 17 in the precisely timed relation to the approach of the thread to the knotter bill. The parts involved are simple in construction and adapted for long service use.

I claim as my invention:

1. ha thread winder, the combination of, means for supporting a length of-thread and advancing the same sidewise along a predetermined path, a finger normally disposed in said path to intercept said thread in its advance, an arm swingable about a fixed axis extending along and spaced laterally from said thread, an elongated lever supporting said finger at one end and fulcrumed intermediate its ends on the free end of said arm whereby to support said finger in said path for movement in an orbit extending transversely of said path, a crank rotatable about a second fixed axis normal to the plane of said orbit and parallel to said first mentioned fixed axis, an eccentric pin on said crank pivotally coupling the crank to the end of said lever opposite said finger, a spring normally urging said crank in one direction but acting to turn the crank in the opposite direction when the crank is moved over-center in the latter direction, a shoulder on said crank facing in said first direction, a retractable pawl normally engagingsaid shoulder under the action of said spring to hold said member in a predetermined position with said finger disposed in said path, and means operable in timed relation to the advance of said thread to turn said crank away from said sidewise along a predetermined path, a finger normally.

position to and beyond an over-center position and thereby release the crank to the action of said spring, the inertia of said crank and the connected parts being sufiicient to carry the crank beyond the opposite over-center position and thereby move said shoulder past said pawl beforev said spring becomes eifective to reverse the direction of turning of the crank. I

2. In a thread winder, the combination of, means for supporting a length of thread and advancing the same crank facing in said first direction, aretractable pawl normally engaging said shoulder under the action of said spring to position said member with said finger disposed in said path and at a predetermined point along said orbit, and means operable in timed relation to the advance of said thread to turn said crank away from said position and over-center and thereby permit the spring to continue the turning, the inertia of said crank and the connected parts being sufiicient to carry the crank beyond the opposite over-center position and thereby move said shoulder past said pawl before reversal of the crank motion by said spring.

3. The combination of, means for supporting a length of thread and advancing the same sidewise along a predetermined path, a finger positioned to intercept said thread in its advance, a member supporting said finger for movement in an orbit disposed to one side of said path and extending transversely thereof, a crank rotatable about a fixed axis normal to the plane of said orbit, means pivotally coupling said member to said crank eccentrically of the latter, a spring normally urging said crank in one direction but acting to turn the crank in the opposite direction when the crank is moved over-center in the latter direction, an abutment on said crank facing in said first projects from the fixed axis thereof along said path but reversely of the direction of travel of said thread.

5. Mechanism as defined by claim 1 in which said lever comprises an L-shaped bell crank.

6. The combination of, means for supporting a length of thread and advancing the same sidewise along a predetermined path, a finger normally disposed in said path to intercept said thread in its advance, a member'supporting said finger for movement in an orbit extending transversely of said path, a crank rotatable about a fixed axis normal to the plane of said orbit, means pivotally coupling the lever and crank eccentrically of the axis of the latter, a spring normally urging said crank in one direction but acting to turn the crank in the opposite direction when the crank is moved over-center in the latter direction, an abutment on said crank facing in said first direction, a retractable pawl normally engaging said abutment under the action of said spring to hold said member in a predetermined position with said finger disposed in said path,

and means operable in timed relation to the advance of said thread to turn said crank away from said position to an over-center position and release the crank to action of said spring whereby to turn the crank beyond the opposite over-center position and move said abutment past said pawl.

References Cited in the file of this patent UNITED STATES PATENTS Colman Dec. 28, 1926 OTHER REFERENCES 

